startup performance

[Eugen Wintersberger <eugen brewster hlphys uni-linz ac at>]

Hi there
 I user Ubuntu Linux (still Edgy and will update in two weeks) with the 
GNOME desktop. After a complete new install of the system GNOME starts up 
pretty fast and shows also a quite nice performance. However, after some 
time (weeks) it is getting slower and slower (especially during startup). 
This effect seems to be independent since I could observe it on all 
releases since 2.12.
Is there any reason why this happens and if yes how can one get GNOME 
becoming faster again?

best regards
  Eugen Wintersberger